Latch mechanism



N. A. WELCH 2,650,122

LATCH MECHANISM Filed March l?, 1949 Aug. 25, 1953 FIG. /.y f"

Ill .A Y: myEN-ron /wc/foLAs A. wam 46 56 54 l IBY l ATTORN EYS Patented ug. 25, 1953 UNITED STATES PATENT (')FFICE 2,650,122 LATCH MECHANISM Nicholas A. Welch, West Hartford, Conn., assignor to The American Hardware Corporation, New Britain, Conn., a. corporation of Connecticut Application March 17,

1949, Serial No. 81,964

10 Claims. (Cl. 292`169) of of the latch.

It is another object to provide a push-buttonoperated latch mechanism wherein two concentric buttons are employed, one of said buttons being used to the exclusion of other said buttons for throwing-oli the latch mechanism.

It is also an object to provlde a push-buttonmechanism may be had by slmple visual observation of the relative axial positioning of said buttons.

Other objects and various further features of the invention will be pointed out or will occur to companying drawings. In said drawings, which show, for illustrative purposes only, preferred forms of the invention:

Fig. 1 is a longitudinal horizontal sectional view of a latch mechanism incorporating features of the invention and shown in application to a door;

Fig. 2 is a fragmentary sectional view of a part of the mechanism of Fig. 1 and in another relationship of parts;

Fig. 3 is a fragmentary sectional View of a modified construction;

Fig. 4 is a sectional view in the plane Ill--fl of Fig. 3,' and Fig. 5 is a view similar to Fig. 3 and illustrating a slight modiiication thereof.

Briey stated, my invention contemplates a push-button-controlled `latch mechanism employing two push buttons. The buttons may be 2 touching the latch or the push buttons) whether or not the latch mechanism has been set. In one buttons are more or less flush; as long as both Referring to Figs. 1 and 2 of the drawings, my invention is shown in application to a cylindrical lock applied to a door IU. The lock. may be built up of generally tubular or cylindrical parts and in the form shown, the assembly includes an outside knob Il and an inside knob I2. Both knobs February 7, 1949.

In accordance with a feature of the invention, push-button means l9-2ll carried by the inside knob l?. may determine the locked or unlocked 3 lugs 24-25 on the blade 22. When the mechanism has been set, as in the case for the relation of parts shown in Fig. l, the blade lug 24 will have entered a limited longitudinal slot 2t in a cylindrical part 21 of the case, and the through-,spindle 2,! and ihence t both knobs H--l2) will then h `yejbeen ldogged against rotation. When the mechanism is thrown off, as in the case of the relation of parts shown in Fig.; V2, the lug 24 will have been displaced (leitward in the sense of Fig. 1) out of the locking ,slot 2 6, so that both knobs ll-TlZ' and thethrough- Vspindle 2l and the blade 22 may freely rotate in Order to operate thelatch 5.. k i It has been explained that the locked or thrown-off condition of theniechanism. maybe determined by the longitudinal placement of the blade 22 (that is, of the blade lug 24) with respeci; to the fixed slot 26. In the form shown, resilient lne'ans: such as a Ac :or'npressi'on spring 2 may normally urge the blade 22 A in an outward directionrthat is, in a throwing-off direction.

The spring 28 Vmay be'contained within 'a cupped member Y29 held in the knob Il and including lguidelmeans', such as longitudinal slots 3l), slidably to receive the bladef2`2. rlhe blade 22 may be permanently connected, as by sweating, to the -outer r`pii'sh-,buttont9 fof the concentric push- 4button means ltil- 2a. The inner push-button 20 may Valso be "rged r'io'r'ri'ia ly in an outward direction by `resilient means, and in the form shown a compression spring 3l (located between a guide ylua 32 on the blade 22 and a reduced end 33 or the push-button V2B) 'may perform this function. For a purpose V which will later be clear, the inrior/push-utton 2li'rrlax'y'carry bracket means 34, and a radially projectingtip thereof may abut a part of the through-'spindle`2'l in order to limit outward displacement of the inner button 2li. Outward l displace vent of the outer Vbutton i9 maybe limited by abutment `of the blade lug 25 with 'the end ofthe innerknb, as at A31.

Inaccordance Ywith a feature of the invention,

one 'of its operative :positions upon push-button actuation, and further actuation of oneof the 'pu's'hsbuttons may erve to throw'off the latch means 'andfhencehto throw oifthe'mechanism; further `latch meansimay be associated with said one button 'and with saidiirst latch means, for

Yemploy ment in the:'tltir'owloff` operation. In the iorinshown the first latching means comprises 1a b'ellfcrank-like'latch member 38 V'pivotally carried by the blade 22 and resiliently urged, las byA a torsion springa'toengage one'end of a slot 49 in the through-spindle 2l in order to ho'l'd'ai depressed'position voi the outer button le. This will be understood to be a set condi- 'the blade lug 24 tion or ythe'mechanism,y with l Y the mechanism against operation fromtheoutside. y

vsem/'ing tov Adog "Whe'rrthe mechanism has been set in this manner,l the inner push-button 20 Awill bev propelled "outwardlypnder'theinfluence of spring 3l, and 'the' secondlatchmeans (in'the form of a leaf spring'llh may engage the downwardly depend- Vv.ing arm of the latch member 38. The leaf spring Alil may be'carried by the bracket 34, and in the form shown it may latch within a notch 42 in the latch member 38. .f In order .to throw off, the mechanism, the in- .ner'` buttonZil need onlyrbe pushed so as to drive the leaf spring V4l Vand ,thus to crank the latch 38 counterclockwise (in the sense of Fig. 1) and rout of engagement with the latching slot 40.

latchmeansfmaybe set tohold'the blade 22 for turing what `engage retaining openings,

leaf springs 54 2 In ordento` setthe nc more, both buttons 13-29 may be pushed in unison until the latch member 38 engages the latching slot 4i), and upon a release of ones finger from both pushfbuttons the latch 38 will serve to hold the outer button le in lwhile permitting the inner button 20 to slide out. In so sliding out, it will be understood that the leaf spring 4|, constimight be called a throw-off latch, willvride under the latch member 38 and into engagement with its latching notch 42.

Referring to Figs. Scand 4 of the drawings, I have shown my invention in application to a twin-push-button latch-setting mechanismV in which a depression of theouter button 45 relatively tothe inner button 46 may serve to throw on the xl'atch'; in Fig. 3, ,the parts 'are 'shown in the latch-set relation. Themechanism'may Vgenerally resemble that of Fig. `l and lit may include spring means (not shown) `for urging th'e llockcontrol blade 41 outwardlyto the left in the sense oi Fig. 3). in Vorder to free kthe mechanism for knob operation. In the structure shown, the outer Yknob l5 .is resi-liently urged outwardly by means of a spring 48'coa'ctin'g withinwardly turned lugs '49 Aof a. through-spindle 50, 'which may generally Vresemble the through-spindle A2l of Fig. l.. YOutward'motio'n of the button 45 may be limited bya circumferential shoulder 51 abutting the inwardly rolled end k52 of the inside 'knob 53.

The inner pushlo'utton4`6 may tbe held latchedv in an Yinner position (the posi-tion o'f Fig. 5) by latch means in the form of a leaf spring or springs 54 having inwardly 'bent latching ends to engagenotches in the shanko the `inner button dit. Oppositely Vdirected lug'sor bent-out ears d3 Yoneachof the latching members 54 may such as the slot 51, in the through=spindle15ll `in order to 'hold .the latch members 54 against longitudinal -mov`ement.

rIn "operation, `the vinner fpush button 45 will 'be an V"outwardly.'extend'e'd position 'irelatively to the outer button 45) when the'mecha 'outside vknob moperation4 ofthe -latch is possible. In order to set be pushed until V`thelatchirrrearis 54 "engages the notches 55' to hold the inne`r`-buttonf5e morey or less nush with the outer'buttbn 45. `A slightly dished thumb-receiving portion t5' inrthe outer button' may serve gto' permit'whatever slight :addif tional pushing of the' inner "button ni-ayA be needed in` rder't'o vset the latch me'anstlior ta locked condition. yIn "ord'ert'o throwpff the latch,^'the outer butto-nat may bee'rigage'd at the edge-and -p'ushed inwardly 'so as to drive the inner shoulders "58 'thereof into aprying A'engagement'" with the leaf springs "5a. It'wi-ll be'understoodthat the prying eifeot'under'the leaf springsfl may dislodge' the; leaf"s'prings' 54 from theV notchesr and that, once such disengagement has been eifectedthe spring behind blade 4l may drive the same (and, hence, the inner push button 4B) into an outwardlyj extended position. l Y A In Fig., 5, I show a slightly 'modified version ofthe ,Fig 'arrangement wherein eachoffthe constituting the latching means is, 'when inside *and for. the latch-setting mechanism is slightly differently formed at the point of engagement with the shank of the inner button 46'; in Fig. 5, the parts are `agam shown in the latch-setrelation.

notches 54, the spring behind blade 41 may shift the inner button 46 outwardly, thus throwing off the mechanism, as will be clear.

It will be appreciated that I have described I claim: l. In a latch device of the character indicated,

an inside knob having an outer exposed face with a bore therein, latch mechanism operated by said position when said mechanism is thus blocked, the other of said buttons proJecting externally 2. A latch device according to claim 1, in which the outer of said push buttons is in an inwardly a push of said inner button.

4. A latch device according to claim 1, in whichI said throw-off means is connected for actuatiori' by a push of said outer button.

5. A latch device according to claim 1, in whicli condition, and in which one of said buttons is in a depressed position when said clogging means has been set.

6. In a latch device of the character indi-` blocking position, and spring means urging said element in the direction of engagement with said abutment. V

8. A latch device according to claim 7, in which said throw-01T means includes a leaf-spring element resiliently engageable with said latch ele- 9. In a latch device of the character indicated, a knob and latch mechanism to be actuated 

